Calculator.



No. 798,206. y PATBNTED AUG'. 29, 1995. J. B. A. PARADIS.

CALCULATOR.

APPLIOATION FILED DBO. a', 1904.

mnsw s GRAHAM co. www.unucmwsws4 msmomu, Lz cA UNITED STATES PATENT OFFICE.

CALCULATOR..

Specification of Letters Patent.

Patented Aug. 29, 1905.

Application filed December 8, 1904. Serial No. 235,916.

To a/Z whom, t may concern:

Be it known that I, JOHN B. A. PARADIS, a citizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesota, have invented a new and useful Calculator, of which the following is a speciiication.

My invention relates to improvements in calculators, and has for its object a simple and inexpensive device for use for multiplying figures.

A further object is an improved calculator which may be carried in the pocket for ready reference and which is easy of manipulation.

In the accompanying drawings, forming part of this specification, Figure l is a side View of my invention. Fig. 2 is an end view. Fig. 3 is a vertical section taken on the line X X of Fig. l, and Fig. 4 is a detail view showing the other side of the calculator.

My invention consists, primarily, of a pocket A and a slide B in said pocket. The pocket is constructed by attaching two pieces 2 and 3 of cardboard or other suitable material with narrow strips 4 and 5 between their vertical edges by wire staples 6 or other suitable means. The slide B is adapted to work freely through the opening 7 and close between the sides and the strips 4 and 5. This slide is a plain piece of cardboard or other suitable material, upon the faces of which are printed vertical columns l0 and 10 substantially midway between its edges. The products 13 are arranged in horizontal and vertical rows, as shown, on both sides of each vertical column of multiplicands. The lower ends ofthe sides have horizontal strips 8 and 9, which are attached to said sides by cement or other suitable means. Upon these strips are printed horizontal rows 11 of multipliers which are caused to register with the products when the slide is adjusted.

It is obvious that the horizontal rows of multipliers may be printed upon the faces of the pocket instead of on the horizontal strips when desired.

This arrangement permits the calculator to be used in the following manner: As an illustration, to multiply eight by forty-nine the slide is moved until the multiplicand adjoins the lower edge of the face of the pocket. The product (three hundred and ninety-two) of this set of figures then appears immediately below the multiplier 8. Should the multiplier be above twenty-live, the pocket is turned to the other side, as shown in Fig. 4. On this latter side the multipliers ranging from 26 to 45 appear, being substantially a continuation of the horizontal rows of multipliers shown in Fig'. 1.

A blank space is preferably left on each of the sides of the slide below all of the tig ures to form a grip 19., by which the slide may be manipulated. When the pocket is held in the hand and used, the two sides thereof are pressed against the slide to hold the same adjusted.

By closing the slide between the sides of the pocket the surfaces of the slide are protected against wear and hard usage, such as when carried in the pocket.

It is obvious that the multipliers and multiplicands and their products may range as high as desired and that the size of the device may be varied to hold as many figures as are used.

Having described my invention, what I claim as new, and desire to protect by Letters Patent, is-

l. A device of the class set forth, consisting of a pocket formed by two sides, suitably fastened together and having their ends open, a slide closing between said sides, and a plurality of transverse rows of figures arranged along the lower edge of one of said sides and between the guiding edges and on the face of said slide, two of said transverse rows constituting multipliers and multiplicands and another row constituting the product of each pair of mulipliers and multiplicands.

2. A device of the class set forth, consisting of a pocket, a slide adapted to close in said pocket and having a grip by which said slide may be moved, and transverse rows of figures, on the lower edge of said pocket and between the vertical edges of said slide, constituting multipliers and multiplicands and another set of figures on said slide constituting the product of and adapted to correspond with each pair of multipliers and multiplicands.

In testimony whereofI have sign ed my name to this specification in the presence of two subscribing witnesses.

JOHN B. A. PARADIS.

Witnesses:

E. M. BonsEL, F. G. BRADBURY.

IOO 

